Yat-chan and Fuku-chan are waiters at the Kaoru Otsuka sake house north of Tokyo. The two are monkeys. They bring hot towels and also serve drinks. From Reuters, where you can also see video:
"Yat-chan first learned by just watching me working in the restaurant. It all started when one day I gave him a hot towel out of curiosity and he brought the towel to the customer," the 63-year-old owner of the tavern, Kaoru Otsuka, told Reuters...Monkey waiters
"We called out for more beer just then and it brought us some beer! It's amazing how it seems to understand human words," said 71-year-old retiree Miho Takikawa, who said she came to the tavern specifically to meet the monkeys.